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In the current context of concern for the improvement and protection of environmental conditions, emphasis is placed on the provision of non-toxic, eco-friendly, renewable biomaterials to replace established chemical substances. Lythri herba is the aerial part of the plant species Lythrum salicaria L., known in the scientific literature especially for its content of tannins and total polyphenols, which highlight its antioxidant, hemostatic, antibacterial and antidiarrheal properties. Chitosan is a biopolymer widely used in industry and medicine due to its abundance in nature, its biodegradability, lack of toxicity and the ease with which it can be transformed into several basic forms (hydrogel, membrane, sponge). The aqueous solutions and membranes obtained in this study by merging these two natural resources were biologically tested in terms of genotoxicity (SOS-Chromo assay), hemolytic activity, thrombin generation activity and bacterial adhesion to reveal outwardly the lack of these properties and their use for medical purposes. The results of the current study attest to the absence of mutagenic and slight hemolyzing properties, thus supporting the possibility of using this extract and membrane in medical and pharmaceutical therapeutic practice. The surface parameters of membranes were examined and important influences at thrombin activity were found. Also, bacterial adhesion results showed a correlation between Lythri herba and chitosan concentrations and membranes’ appearances (swelling, stability). The results show that the membranes could be a promising material for biomedical applications.

The interest upon CO2 concentrations introduced in the atmosphere by human activities enhances year after year because of the consequences on the atmosphere, land and oceans. Many studies showed that changes in the ocean carbon cycle are due to the absorption of anthropogenic CO2 from the atmosphere. The increase of CO2 has been correlated with the pH falling of seawaters, promoting a critical process known as acidification. Ocean acidification could modify many biochemical cycles and functioning of marine organisms. The aim of this paper is to demonstrate the chemistry behaviour of CO2 on seawaters. Once dissolved in seawater, CO2 reacts with water to form carbonic acid (H2CO3). Ocean stores CO2 as dissolved inorganic carbon (DIC) which remains in the form of dissolved CO2 and H2CO3, while the rest is in the form of HCO3- and CO3 2-. Adding CO2 to seawater, thus increase HCO3- that bring about a decrease in ocean water pH by increasing H+ concentration. [ABSTRACT FROM AUTHOR]